Highly educated, quality-conscious parents lose a lot of sleep deciding where to send their kids to school. They pore over test scores. They fret over where to move. And they even pony up for private school tuition.

Yet in light of what we know about educational achievement, their obsessive quests are almost entirely unnecessary. And worse, their pursuits are undermining the broader aim of equity.

Whatever the rhetoric about a decline in public education, most schools are actually pretty good. How do we know? Just ask their clients. As polling data reveal, the vast majority of parents are very satisfied with the schools their children attend. And their high levels of satisfaction have been consistent over the past several decades.

Even if that weren’t the case, though, the fact remains that schools don’t matter as much as people think. That isn’t to say that schools don’t matter. They certainly do. But school factors are vastly outweighed by out-of-school factors, which account for roughly 60 percent of achievement outcomes. Relative to family background characteristics, school factors pale in comparison, explaining only about 20 percent of achievement.

What this means, in a nutshell, is that the parents who may be fretting the most about school quality—generally, a well-educated group of adults with access to various forms of capital—have the least to worry about.

Parents, for instance, are the driving force in a child’s academic orientation and self-concept. Consequently, young people with parents who care about education will, themselves, care about education. This happens because children absorb their parents values. But it also happens because children are strongly influenced by community expectations. In short, if young people are surrounded by people who expect them to succeed in school, they’ll work hard to meet that expectation.

Parents also determine the degree to which their children enter school each day prepared to build new knowledge. Remember, schools don’t fill student skulls like gas tanks. If they did, the quality of the fuel would be of primary concern. Instead, schools are learning environments in which children participate at different levels of cognitive engagement. Rather than gas tanks, then, imagine sponges. Children with active and education-conscious parents come to school ready to learn—entering Kindergarten with pre-reading skills, huge capacities for language, and early mathematical reasoning abilities. Whatever the particular nature of the learning environment, such students are well-prepared to soak up new knowledge.

Finally, children spend far more time at home than in school—roughly twice as many waking hours. This is important for two reasons. First, it means that the home environment matters greatly in a child’s educational development. Going to the library, for instance, does far more for a kid than plopping her down in front of the television. Second, it means that some children are far more prepared to get something out of their school experiences. Most students, after all, wring only a fraction of school’s value from it. Some parents, however, help their children get more out of school by talking with them, cultivating good study habits, setting up quiet spaces for homework, and encouraging their children to read.

Highly educated parents inclined to obsess over school quality, in other words, are likely to be exactly the kinds of parents whose children will thrive no matter what school they go to. But they are also the most likely to fall for the distorted allure of suburban and private schools. And there’s the rub. Because when they do, they pull resources out of schools where they might matter, only to pile them up in wasteful overabundance in relatively homogenous schools.

Do schools need kids with these kinds of parents? No. Such students are no more special than any other young person. But a relatively equal distribution of different kinds of students across schools is critical to ensuring the kinds of truly diverse environments children thrive in. And in this age of testing and accountability, a rich mix of students in every school also helps ensure that teachers aren’t blamed for factors completely beyond their control.

So should quality-conscious parents blindly send their children to any school? Of course not. Some schools, particularly those plagued by hyper-segregation, are overwhelmed with challenges and may be unfit learning environments. But as long as a school is diverse and safe, as long as it offers a rich and varied curriculum, and as long as it hasn’t given up the arts in favor of test prep, most kids will do just fine.

Instead of fixating on standardized test scores or angling for admission to a tony private school, then, well-educated and quality-conscious parents should direct their energies into picking a highly diverse public school—one with students from all kinds of families. Their kids will do just as well as they would have elsewhere. In fact, learning in truly diverse environments, they might do even better. And the schools they attend will become richer and more diverse as a result. Everyone wins.

Correction: The original version had a headline that said college instead of school. This is about K-12 education.